Fluid evacuation system with two-way communication filter

ABSTRACT

An evacuation system includes at least one fluid intake, at least one fluid outlet, at least one operational component such as an evacuation motor, and a first read/write device such as an RFID tag for transmitting, receiving, or storing information. The evacuation system also includes a filter having a second read/write device for transmitting information to the first read/write device. A microcontroller, which is in functional communication with the first read/write device and the operational component, interprets the information received by said first read/write device and controls the operational component based on said interpreted information.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

The present application is a continuation of U.S. patent application Ser. No. 11/398,285, filed Apr. 4, 2006, now U.S. Pat. No. 7,761,188 B2, which claims the benefit of U.S. Provisional Application No. 60/668,126, filed Apr. 4, 2005, both of which are hereby incorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic drawing of components of an embodiment of an evacuation system connected to the microcontroller;

FIG. 2 is a schematic drawing of one embodiment of a read/write circuit functionally connected to a filter;

FIG. 3 is a schematic drawing of another embodiment of a read/write circuit functionally connected to a filter;

FIG. 4 is a circuit diagram of a RS-232 communication circuit of an evacuation system;

FIG. 5 is a circuit diagram of a two way read/write circuit connected to a microcontroller of an evacuation system;

FIG. 6 is a circuit diagram showing a display panel and a two-way read/write circuit connected to a microcontroller of an evacuation system; and

FIG. 7 illustrates screen shots displayed on a display panel of an evacuation system.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Initially, it should be appreciated that like drawing numbers on different drawing view identify identical structural elements. It also should be appreciated that figure proportions and angles are not always to scale. Further, it should be understood that the evacuation system is not limited to the disclosed embodiments. Various modifications and equivalent arrangements may be included within the spirit and scope of the appended claims.

Referring to the drawings, FIG. 1 is a partial schematic drawing of an evacuation system 10 for evacuating suspended particulates from a fluid stream. It should be understood that the fluid stream may be comprised of liquids, gases, and/or solids. Further, the suspended particles may be visible or microscopic particles; organic or inorganic matter. In one embodiment, the suspended particles in a fluid stream are in the form of smoke. Evacuation system 10 includes at least one fluid intake, at least one exhaust outlet and an evacuation motor unit (not shown). As shown, a microcontroller 11 is in functional communication with components of evacuation system 10 such as input signal latches 13, output signal latches 14, an alternate circuit (A/C) synchronization system 15, a motor drive 16 and a remote switch interface 17. Microcontroller 11 is also in functional communication with a display screen 18. In addition, microcontroller 11 is functionally connected to a two-way read/write circuit 20. In the embodiment shown in FIG. 1, read/write circuit 20 includes an antenna 21 which may be present if read/write circuit 20 is a radio frequency identification tag (“RFID”) reader/writer. The read/write circuit 20 may be based on the ISO 15693 standard for communicating with tags at 13.56 MHz. Further, the interface between microcontroller 11 and read/write circuit 20 may include a 3-wire serial interface having a bi-directional clock controlled by microcontroller 11 during command/data write operations and by read/write circuit 20 during data read operations. In one embodiment, evacuation system 10 includes a control panel (not shown). The control panel and display screen 18 may combined into one integral component. In anther embodiment, evacuation system 10 is in functional communication with a filter 22 which includes a second two-way read/write circuit such as RFID tag 23.

A suitable read/write circuit component is the TI S6700 ASIC from Texas Instruments or similarly equivalent devices. In an alternate embodiment, read/write circuit 20 may include a direct-wired connection between microcontroller 11 and a downstream component, such as filter 22.

Microcontroller 11 contains at least one program configured to control the functionally connected components as well as, when necessary, determining changes in functional or operational parameters of the functionally connected components. As used herein the phrases “functionally connected” shall mean that components, for example, microcontroller 11 and read/write circuit 20, are connected in such a way that signals, data, controls and other applicable modes of information are transmitted therebetween using either suitable direct wired connections or a form of wireless or radio transmission and reception. In one embodiment, in which read/write circuit 20 is an RFID tag reader/writer, an antenna is used to functionally communicate with an RFID tag on another component. Microcontroller 11 may include an external electrically erasable programmable read-only memory (EEPROM) to hold the required programs. An internal EEPROM may be used as it requires fewer I/O pins and makes available more memory. In an alternate embodiment, microcontroller 11 may be in functional communication with a data port, such as a USB connection, to allow changes or replacement of a program.

In another alternate embodiment, read/write circuit 20 and read/write circuit of filter 22 may transfer information using short-distance radio communication. According to this kind of radio communication method, cordless communication between equipment and a terminal can be established. For example, short-distance radio communication can be used for the following: data exchange between pieces of portable information equipment; and transmission of data and sound between a main body of a telephone (or a portable music player) and a headset, between a main phone and a cordless handset, and between others. One representative type of short-distance radio communication is Bluetooth.

FIGS. 2 and 3 illustrate schematically two configurations of read/write circuit 20 functionally connected to filter 22 and RFID tag 23. In FIG. 2, antenna 21 is arranged such that the planes formed by antenna 21 and RFID tag 23 are parallel to each other. Although this configuration allows for two-way communication between distances of up to 8 inches, the presence of metal or other conductive material between antenna 21 and tag 23 interferes with communication between the two components.

FIG. 3 illustrates an orientation in which antenna 21 is looped around a filter housing (not shown) in a substantially perpendicular orientation in relation to tag 23. While this orientation reduces effective communication range, it allows for designs such that tag 23 is about 0.5 inch from at least a part of antenna 21. As shown in FIG. 2, antenna 21 is arranged parallel to at least a part of tag 23. Suitable RFID tags include the TI-IT HF-I transponder family of tags from Texas Instruments. Persons of ordinary skill in the art will recognize that more than one RFID tag 23 may be used with filter 22. Also, the two-way readlwrite circuit of filter 22, such as RFID tag 23, can be used to transmit command and control instructions to microcontroller 11.

FIG. 7 is a collection of screen shots presented on display screen 18, such as an LCD screen, to inform the system user of various operational or structural parameters or data including, but not limited to, type of filter used, filter life remaining, filter life consumed, evacuation motor suction setting, filter lot number, filter manufacturing date, authentication code(s), evacuation motor brush life, and an error message. It will be obvious to those skilled in the art that other messages, including set up parameters such as off/standby/on message(s), flow rate and/or motor speed, mode selection, and filter overuse (use past rated filter life) may be displayed on the display screen. An authentication code (for example, to allow or disallow operation of the evacuation system), first written into a filer read/write circuit, may be transmitted to microcontroller 11 to command that a certain flow rate or flow rate range be used for that filter. It will be recognized that the functional communication between RFID tag 23 of filter 22 and microcontroller 11 through read/write circuit 20 enables the above operation and/or structural parameters to be transmitted to and from filter 22 and microcontroller 11.

Typically, display screen 18 may be mounted on a evacuation boom in an easily visible position such as that disclosed in U.S. Pat. No. 6,524,307 to Palmerton, et al. Alternatively, display screen 18 may be detached and mounted on a wall, in a separate control room, operating room or on a stand-alone evacuation unit that intakes air to filter smoke and/or particulate matter and evacuates it back into a room. In one embodiment, display screen 18 is integral with an evacuation system control panel.

FIG. 6 is a circuit diagram showing several of the circuits leading from microcontroller 11. Read/write circuit 20 is shown to include antenna 21. Display screen 18 is also shown connected to microcontroller 11.

Typically, microcontroller 11 contains programming to calculate and display the remaining filter life. The established or rated filter life is written into RFID tag 23, along with such information as filter type or name, manufacturer, and manufacturing lot number. When a new filter is inserted into the evacuation system, microcontroller 11 reads and stores this infonnation through read/write circuit 20 after powering RFID tag 23 through antenna 21 or read/write circuit 20. Some or all the information is displayed as seen in the screen shots of FIG. 7. Displayed calculations such as remaining filter life may be based on a simple calculation loop. Established filter life may be based on a particular evacuation motor speed or intake flow rate which is a function of evacuation motor speed. At a preset time interval, the motor speed or flow rate is sensed or calculated and recorded by the program in microcontroller 11. In the same operation, the number of minutes or seconds is subtracted from the rated filter life. Thus, if a filer life for a particular filter is rated at 10 hours (600 minutes), after one minute of operation, remaining filter life would be 559 minutes. In one embodiment, this calculation may be adjusted by actual flow rate. Thus, if the flow rate used to establish the rated filer life is 10 CFM, a flow rate of 5 CFM would increase filter life to 20 hours which would be calculated and stored in microcontroller 11 memory and displayed. Similarly, if the actual flow rate is 20 CFM, the actual filter life would be 300 minutes (5 hours). In one embodiment, if an evacuation system is operated at different flow rates, the displayed remaining filter life is based on the current operating flow rate.

In an alternate embodiment, filter life may be based on time of use. In this embodiment, microcontroller 11 and/or RFID tag 23 may include a clock or timer function to determine the length of time of filter use.

Each recorded change in filter life is also transmitted through read/write circuit 20 to RFID tag 23 where it may be saved. Consequently, if filter 22 is moved from one evacuation unit to another compatible unit, that second unit would read the remaining filter life on the transferred filter. Remaining filter life may be displayed in several ways, including but not limited to, a percentage of rated filter life, actual remaining filer life, and consumed filter life. Similarly, diagnostic parameters, such as motor brush life and filter history, may be calculated and displayed using similar calculations.

The microcontroller 11 and/or RFID tag 23 may also include a reset feature in which an evacuation system is powered into a standby or operational mode but no smoke or other particulates are actually evacuated through filter 22. In such a situation, a recorded filter life may be reset to the full rated life. Other possible displays include but are not limited to, error messages indicating filter or diagnostic errors, authentication codes, filter history, evacuation flow rate, suction speed, and/or motor speed. Some or all of these operational and structural parameters may be transmitted and saved onto RFID tag 23 or equivalent components.

In one embodiment, RFID tag 23 of filter 22 contains control information that when transmitted to microcontroller 11, details particular operational parameters to be enabled. For example, certain filters 22 may be designed for certain flow rates. Commands transmitted from RFID tag 23 may then be transmitted to microcontroller 11 to operate the evacuation motor at those specific flow rates or within a certain flow rate range.

Up to this point, the evacuation system was described in detail with reference to specific embodiments. The described embodiments were presented in the form of exemplification and should not be interpreted in a limited manner. Changes and modifications to these embodiments should be readily apparent to those having ordinary skill in art. 

1. A method for controlling a system for evacuating suspended particulates from a fluid having at least one fluid intake, at least one fluid outlet, a first read/write device, and a controller coupled to said first read/write device, said method comprising: inserting a filter into said evacuation system, said filter having a rated filter life and said filter including a RFID tag having said rated filter life stored thereon; transmitting said rated filter life from said RFID tag to said first read/write device; measuring the flow into said filter; operating said evacuation system for a first time period; determining remaining filter life by subtracting said first time period from said rated filter life; and adjusting said remaining filter life with said controller as a function of said flow into said filter; wherein said remaining filter life is calculated as a function of flow into said filter and as a function of time.
 2. The method according to claim 1 further comprising displaying said remaining filter life on a display screen coupled to said controller.
 3. A method for controlling a system for evacuating suspended particulates from a fluid having an RFID tag reader and a controller coupled to said RFID tag reader, said method comprising: inserting a filter into said evacuation system, said filter operable only within an established flow range; said filter having an associated RFID tag which contains information identifying said established flow range; transmitting said information identifying said established flow range from said RFID tag to said RFID tag reader; controlling an evacuation motor with said controller such that said evacuation motor operates only within said established flow range.
 4. A method for controlling a system for evacuating suspended particulates from a fluid having an RFID tag reader and a controller coupled to said RFID tag reader, said method comprising: inserting a filter into a first evacuation system, said filter having a rated filter life and said filter having a RFID tag with said rated filter life stored thereon; measuring the flow into said filter during a first time period; determining remaining filter life as a function of said flow into said filter; storing said remaining filter life information on said RFID tag; removing said filter from said first evacuation system and inserting said filter into a second evacuation system, said filter retaining said remaining filter life information determined in said first evacuation system.
 5. A method for controlling a system for evacuating suspended particulates from a fluid having an RFID tag reader and a controller coupled to said RFID tag reader, said method comprising: inserting a filter into said evacuation system, said filter having an RFID tag for storing filter life information thereon; measuring the flow of a fluid into said filter during a first time period; determining remaining filter life as a function of said flow into said filter during said first time period; storing said remaining filter life on said RFID tag; determining whether suspended particulates are present in said fluid during said first time period; if suspended particulates are not present in said fluid during said first time period, resetting said stored remaining filter life to its value prior to said first time period; and measuring the flow of a fluid into said filter during a second time period.
 6. The method according to claim 5 wherein said suspended particulates comprise smoke or moisture. 